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        <p>Library Version 11.2.5.3</p>
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                Berkeley DB Command Line Utilities
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    <div class="sect1" lang="en" xml:lang="en">
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            <h2 class="title" style="clear: both"><a id="db_checkpoint"></a>db_checkpoint</h2>
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      <pre class="programlisting">db_checkpoint [-1Vv] [-h home]
    [-k kbytes] [-L file] [-P password] [-p min]  </pre>
      <p>
         The <span class="command"><strong>db_checkpoint</strong></span> utility is a daemon process that monitors the
         database log, and periodically calls 
            <a class="xref" href="txncheckpoint.html" title="DB_ENV-&gt;txn_checkpoint()">DB_ENV-&gt;txn_checkpoint()</a>
         to checkpoint it.
    </p>
      <p>
        The options are as follows:
    </p>
      <div class="itemizedlist">
        <ul type="disc">
          <li>
            <p>
              <span class="bold"><strong>-1</strong></span>
            </p>
            <p>
                 Force a single checkpoint of the log (regardless of whether or not
                 there has been activity since the last checkpoint), and then exit.    
            </p>
            <p>
                 When the <span class="bold"><strong>-1</strong></span> flag is specified, the
                 <span class="command"><strong>db_checkpoint</strong></span> utility will checkpoint the log even if unable to find
                 an existing database environment.  This functionality is useful when
                 upgrading database environments from one version of Berkeley DB to
                 another.
            </p>
          </li>
          <li>
            <p>
                 <span class="bold"><strong>-h</strong></span>
            </p>
            <p>
                 Specify a home directory for the database environment; by default, the
                 current working directory is used.
            </p>
          </li>
          <li>
            <p>
                 <span class="bold"><strong>-k</strong></span>
            </p>
            <p>
                 Checkpoint the database at least as often as every <span class="bold"><strong>kbytes</strong></span> of log file are written.
            </p>
          </li>
          <li>
            <p>
                 <span class="bold"><strong>-L</strong></span>
            </p>
            <p>
                 Log the execution of the <span class="command"><strong>db_checkpoint</strong></span> utility to the specified file
                 in the following format, where <span class="emphasis"><em>###</em></span> is the process
                 ID, and the date is the time the utility was started.
             </p>
            <pre class="programlisting"> db_checkpoint: ### Wed Jun 15 01:23:45 EDT 1995 </pre>
            <p>    
                 This file will be removed if the <span class="command"><strong>db_checkpoint</strong></span>
                 utility exits gracefully.
            </p>
          </li>
          <li>
            <p>
                 <span class="bold"><strong>-P</strong></span>
            </p>
            <p>
                Specify an environment password.  Although Berkeley DB utilities overwrite password
                strings as soon as possible, be aware there may be a window of vulnerability on
                systems where unprivileged users can see command-line arguments or where utilities
                are not able to overwrite the memory containing the command-line arguments.
            </p>
          </li>
          <li>
            <p>
                 <span class="bold"><strong>-p</strong></span>
            </p>
            <p>
                 Checkpoint the database at least every <span class="bold"><strong>min</strong></span> minutes
                 if there has been any activity since the last checkpoint.
            </p>
          </li>
          <li>
            <p>
                 <span class="bold"><strong>-V</strong></span>
            </p>
            <p>
                 Write the library version number to the standard output, and exit.
            </p>
          </li>
          <li>
            <p>
                 <span class="bold"><strong>-v</strong></span>
            </p>
            <p>
                 Write the time of each checkpoint attempt to the standard output.
            </p>
          </li>
        </ul>
      </div>
      <p>
         At least one of the <span class="bold"><strong>-1</strong></span>, <span class="bold"><strong>-k</strong></span>, and <span class="bold"><strong>-p</strong></span>
         options must be specified.
    </p>
      <p>
         The <span class="command"><strong>db_checkpoint</strong></span> utility uses a Berkeley DB
                environment (as described for the <span class="bold"><strong>-h</strong></span>
                option, the environment variable 
                <span class="bold"><strong>DB_HOME</strong></span>, or because the utility
                was run in a directory containing a Berkeley DB
                environment). 
         In order to avoid environment corruption when using a Berkeley DB
         environment, <span class="command"><strong>db_checkpoint</strong></span> should always be given the chance to detach
         from the environment and exit gracefully.  To cause <span class="command"><strong>db_checkpoint</strong></span> to
         release all environment resources and exit cleanly, send it an
         interrupt signal (SIGINT).
    </p>
      <p>
         The <span class="command"><strong>db_checkpoint</strong></span> utility does not attempt to create the Berkeley DB
         shared memory regions if they do not already exist.  The application
         that creates the region should be started first, and once the region
         is created, the <span class="command"><strong>db_checkpoint</strong></span> utility should be started.
    </p>
      <p>
         The <a class="xref" href="txncheckpoint.html" title="DB_ENV-&gt;txn_checkpoint()">DB_ENV-&gt;txn_checkpoint()</a>
         method is the underlying method used by the <span class="command"><strong>db_checkpoint</strong></span> utility. See
         the <span class="command"><strong>db_checkpoint</strong></span> utility source code for an example of using 
         <code class="methodname">DB_ENV-&gt;txn_checkpoint()</code> in a IEEE/ANSI Std 1003.1 (POSIX) environment.
    </p>
      <p>
         The <span class="command"><strong>db_checkpoint</strong></span> utility exits 0 on success, and &gt;0 if an error
         occurs.
    </p>
      <div class="sect2" lang="en" xml:lang="en">
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            <div>
              <h3 class="title"><a id="idp55074952"></a>Environment Variables</h3>
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        <div class="sect3" lang="en" xml:lang="en">
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              <div>
                <h4 class="title"><a id="idp55075264"></a>DB_HOME</h4>
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          <p>
                          If the <span class="bold"><strong>-h</strong></span> option is not specified and
                          the environment variable DB_HOME is set, it is used as the path of the
                          database home, as described in the 
                          <a class="xref" href="envopen.html" title="DB_ENV-&gt;open()">DB_ENV-&gt;open()</a> method.
                     </p>
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